Adds an initial limited implementations of geo features to SQL. This implementation is based on the [OpenGIS® Implementation Standard for Geographic information - Simple feature access](http://www.opengeospatial.org/standards/sfs), which is the current standard for GIS system implementation. This effort is concentrate on SQL option AKA ISO 19125-2.
## Queries that are supported as a result of this initial implementation
### Metadata commands
- `DESCRIBE table` - returns the correct column types `GEOMETRY` for geo shapes and geo points.
- `SHOW FUNCTIONS` - returns a list that includes supported `ST_` functions
- `SYS TYPES` and `SYS COLUMNS` display correct types `GEO_SHAPE` and `GEO_POINT` for geo shapes and geo points accordingly.
### Returning geoshapes and geopoints from elasticsearch
- `SELECT geom FROM table` - returns the geoshapes and geo_points as libs/geo objects in JDBC or as WKT strings in console.
- `SELECT ST_AsWKT(geom) FROM table;` and `SELECT ST_AsText(geom) FROM table;`- returns the geoshapes ang geopoints in their WKT representation;
### Using geopoints to elasticsearch
- The following functions will be supported for geopoints in queries, sorting and aggregations: `ST_GeomFromText`, `ST_X`, `ST_Y`, `ST_Z`, `ST_GeometryType`, and `ST_Distance`. In most cases when used in queries, sorting and aggregations, these function are translated into script. These functions can be used in the SELECT clause for both geopoints and geoshapes.
- `SELECT * FROM table WHERE ST_Distance(ST_GeomFromText(POINT(1 2), point) < 10;` - returns all records for which `point` is located within 10m from the `POINT(1 2)`. In this case the WHERE clause is translated into a range query.
## Limitations:
Geoshapes cannot be used in queries, sorting and aggregations as part of this initial effort. In order to fully take advantage of geoshapes we would need to have access to geoshape doc values, which is coming in #37206. `ST_Z` cannot be used on geopoints in queries, sorting and aggregations since we don't store altitude in geo_point doc values.
Relates to #29872
The CircuitBreaker was introduced as means of preventing a
`StackOverflowException` during the build of the AST by the parser.
The ANTLR4 grammar causes a weird behaviour for a Parser Listener.
The `enterEveryRule()` method is often called with a different parsing
context than the respective `exitEveryRule()`. This makes it difficult
to keep track of the tree's depth, and a custom Map was used as an
attempt of matching the contextes as they are encounter during `enter`
and during `exit` of the rules.
This approach had 2 important drawbacks:
1. It's hard to maintain this custom Map as the grammar changes.
2. The CircuitBreaker could often lead to false positives which caused
valid queries to return an Exception and prevent them from executing.
So, this removes completely the CircuitBreaker which is replaced be
a simple handling of the `StackOverflowException`
Fixes: #41471
* SQL: [Docs] Add example for custom bucketing with CASE
Add a TIP on how to use CASE to achieve custom bucketing
with GROUP BY.
Follows: #41349
* address comments
* address comment
Implement a more trivial case of the CASE expression which is
expressed as a traditional function with 2 or 3 arguments. e.g.:
IIF(a = 1, 'one', 'many')
IIF(a > 0, 'positive')
Closes: #40917
Implement the ANSI SQL CASE expression which provides the if/else
functionality common to most programming languages.
The CASE expression can have multiple WHEN branches and becomes a
powerful tool for SQL queries as it can be used in SELECT, WHERE,
GROUP BY, HAVING and ORDER BY clauses.
Closes: #36200
After `TIME` SQL data type is introduced, implement
`CURRENT_TIME/CURTIME` functions similarly to CURRENT_TIMESTAMP
that return the system's current time (only, without the date part).
Closes: #40468
A full format for a DATETIME would be:
`2019-03-30T10:20:30.123+10:00` which is 29 chars long.
For DATE a full format would be: `2019-03-30T00:00:00.000+10:00`
which is also 29 chars long.
* document ODBC's extra connection string parameters
Document the connection string parameters that are currently not
configurable from the GUI.
Add a note about SmartScreen possible warning on driver MSI
installation.
Add a note about the TLS certificate file not being supported as bundled
or password-protected.
* rephrasing and restructuring the list of params
- addressing PR review notes
* rephrasings and reference linking
- addressing PR review notes
To avoid having to specify each spec by hand (which can miss specs to be
added), the test infrastructure now performs classpath discovery so that
each spec added, is automatically considered.
Relates #40358
For cases where fields can have multi values, allow the behavior to be
customized through a dedicated configuration field.
By default this will be enabled on the drivers so that existing datasets
work instead of throwing an exception.
For regular SQL usage, the behavior is false so that the user is aware
of the underlying data.
Fix#39700
* SYS COLUMNS will skip UNSUPPORTED field types in ODBC and JDBC, as well.
NESTED and OBJECT types were already skipped in ODBC mode, now they are
skipped in JDBC mode, as well.
This defaults to "true" (current behavior) and will throw an exception
if there is a property that cannot be recognized. If "false", it will
ignore anything unrecognizable.
`<expression>::<dataType>` is a simplified altenative syntax to
`CAST(<expression> AS <dataType> which exists in PostgreSQL and
provides an improved user experience and possibly more compact
SQL queries.
Fixes: #38717
Introduce client-side sorting of groups based on aggregate
functions. To allow this, the Analyzer has been extended to push down
to underlying Aggregate, aggregate function and the Querier has been
extended to identify the case and consume the results in order and sort
them based on the given columns.
The underlying QueryContainer has been slightly modified to allow a view
of the underlying values being extracted as the columns used for sorting
might not be requested by the user.
The PR also adds minor tweaks, mainly related to tree output.
Close#35118
Currently aggregate functions can operate only directly on fields.
They cannot be used on top of scalar functions as painless scripting
is currently not supported.
